This invention relates generally to apparatus handling edge-coded documents, such as cards, microfiche jackets, and the like. The present invention is adapted for use with both equipment for notching the edges of documents to code them and with equipment for selecting documents bearing a selected code from a group of randomly-stored documents bearing a large number of different codes. The invention is more particularly directed to an improved interposer mechanism for positioning elongated bars which are utilized in such apparatus to establish a code pattern for selecting cards or to actuate punches for notching a code pattern along the edge of a card.
The interposer of this invention may be employed advantageously with many different types of sorting or coding apparatus. One general type of apparatus with which it is particularly adapted to be utilized is disclosed in Robert D. Parry Reissue U.S. Pat. No. Re. 23,762 for "Article Selection System." In order to provide a better appreciation of the mode of operation and advantages of the present interposer, it will be described in relation to apparatus generally of the type disclosed in the above identified Parry patent. The present interposer construction is also especially adapted for use in a combined selector and card puncher of the type disclosed in the copending application of Richard C. O'Brien entitled "Combined Article Selector and Coder", Ser. No. 596,915, filed July 17, 1975.
In general, a document selection or retrieval system of the type disclosed in the Parry patent is adapted to select mechanically from a group of randomly-stored, edge-notched cards those cards bearing a predetermined coding. In the Parry-type of apparatus, a group of cards are supported parallel to one another on their notched edges. The support surface for the cards comprises a platen having a plurality of elongated slots corresponding in number to the possible notch sites of the cards. These slots extend perpendicular to the edges of the cards. Each slot houses a coding bar which can be positioned in a retracted position below the level of the platen where it is completely disengaged from the cards, or in a raised position in which it extends a fraction of an inch above the platen. In accordance with the disclosure of the Parry patent, the cards include a plurality of serrations, or teeth, along their lower edges. Selected teeth are cut to form the notches corresponding to the desired code.
In order to select the card or cards bearing a predetermined code, bars in the positions corresponding to the code are elevated in response to electrical input signals generated when an operator pushes buttons corresponding to the selected code. These bars enter the spaces in the cards between adjacent teeth.
The selector described above also includes a rather complex mechanism for moving selected coding bars from their retracted position to a raised position in response to electrical input signals from the keyboard. This mechanism includes a plurality of solenoids mounted on a movable carriage. Each solenoid operates a linkage effective to engage and shift the adjacent code bar when the solenoid is energized. After one set of blades has been set, the carriage is advanced to bring the solenoid-actuated linkages adjacent to a new group of code bars. Selected solenoids are energized to set the new bars. Thereafter, the carriage is again advanced to bring the linkages adjacent to a new set of bars and the desired solenoids energized. This is repeated until all of the chosen bars are set. Once all of the selected coding bars have been raised, a magnetic member in contact with magnetically-responsive chips on the upright edges of the ends is shifted away from the card deck to slide the selected card or cards transversely across the platen.
While the mechanism described in the above-identified patent has proved to be reliable for separating selected edgenotched cards from a plurality of such cards, it is subject to certain drawbacks. In the first place, the code bar setting mechanism is costly because of its mechanical complexity and the relatively close tolerances required. In addition to the cost, the movable carriage and its escapement-type shifting mechanism require maintenance to ensure reliable operation. Furthermore, the overall mechanism is relatively noisy in operation.
In view of the foregoing shortcomings associated with prior art code bar setting mechanisms, it is a primary objective of this invention to provide a novel interposer mechanism for positioning code bars, or the like, in a document selection system which is of extremely simple construction and requires relatively low tolerance parts.
It is a further objective of this invention to provide an interposer mechanism for positioning code bars, or the like, which is less expensive to produce and is more trouble-free in operation.
It is another objective of the invention to provide an interposer for positioning code bars, or the like, in a document retrieval apparatus which is compact in size and quiet in operation.
These and other objects and advantages of this invention will become more readily apparent from a consideration of the following detailed description of a preferred embodiment of the invention: